BACKGROUND
1. Technical Field
The present disclosure relates to key structures, particularly to a multi-contact key structure.
2. Description of Related Art
Portable electronic devices such as mobile phones and personal digital assistants (PDA) are widely used. Keys that can produce different results according to how they are pressed are herein called multi-contact keys. For example, a key or button of device that is pressed part way down to focus a camera then pressed all the way down to take a picture after focusing is done is one such multi-contact key.
However, the typical structure of the multi-contact key is complex and not easy to assemble.
Therefore, there is room for improvement within the art.
BRIEF DESCRIPTION OF THE DRAWINGS
Many aspects of the present key structure can be better understood with reference to the following drawings. The components in the various drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present battery cover mechanism. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the diagrams.
FIG. 1 is a disassembled view of the key structure, according to an exemplary embodiment.
FIG. 2 is an assembled view of the resilient member of the key structure shown in FIG. 1.
FIG. 3 is a section view of electronic device housing assembled the key structure shown in FIG. 1.
FIG. 4 is a section view of key structure shown in FIG. 1 in a first using state.
FIG. 5 is a section view of key structure shown in FIG. 1 in a second using state.
DETAILED DESCRIPTION OF THE EMBODIMENT
FIG. 1 shows a key structure 100, which can be used in mobile phones and other portable electronic devices, such as personal digital assistants (PDAs), digital cameras, etc. The key structure 100 includes a pressing body 10, a resilient member 20, a dome member 30 and a circuit board 40. The pressing body 10 includes a base rim 12 and a protrusion 14 protruding from the base rim 12.
Referring further to FIG. 3, the resilient member 20 includes a cover board 22, a connecting wall 24 extending at a slant from the sidewall of the cover board 22, and a peripheral rim 26 connected to the bottom of the connecting wall 24 and substantially perpendicular to the cover board 22. The base rim 12 can receive the cover board 22 therein and engaged to each other using adhesive. The connecting wall 24 is thin and the slant relative to with the cover board 22 at an acute angle α. The angle α can be about 40 to 50 degree.
Referring to FIG. 2, the cover board 22, the connecting wall 24 and the peripheral rim 26 enclose a chamber 28. The chamber 28 has a column 222 formed at the center of the bottom without extending out of the chamber 28. The bottom of the chamber 28 further has a plurality of conducting films 29 formed (e.g., printed or coated) thereon. The conducting films 29 are crossed and extend to the peripheral rim 26 to form a plurality of first connecting points 292. Four first connecting points 292 are located on the connecting sections of the conducting films 29 and the peripheral rim 26 in the present embodiment. The intersection of the conducting films 29 is located on the top of the column 222 and thus forms a second connecting point 294 thereon. The first connecting points 292 and the second connecting point 294 are configured for electronically connecting with the terminals of the circuit board 40.
The dome member 30 has an arch portion 32 formed at the center and a peripheral portion 34 around the arch portion 32. The arch portion 32 forms a touching point 322 at the center corresponding to the second connecting point 294 and configured for engaging with the second connecting point 294.
The circuit board 40 forms four first terminals 42, four second terminals 44 and a third terminal 46. The first terminals 42 correspond to the first connecting points 292 of the resilient member 20. The second terminals 44 are configured for electrically connecting to the peripheral portion 34. The third terminal 46 corresponds to the touching point 322 of the dome member 30.
Referring to FIG. 3, when the key structure 100 is assembled in the housing 50, the pressing body 10, resilient member 20, and the dome member 30 are positioned between the housing 50 and the circuit board 40. The dome member 30 is mounted to the circuit board 40, the peripheral portion 34 covers the first terminals 42, the second terminals 44 and the third terminal 46, and the peripheral portion 34 electronically connects with the second terminals 44. The touching point 322 of dome member 30 aligns with the third terminal 46. The resilient member 20 covers the dome member 30 and thus the dome member 30 is received in the chamber 28 of the resilient member 20. The peripheral rim 26 of the resilient member 20 abuts the periphery of the circuit board 40, the first connecting points 292 conductively contact the first terminals 42 of the circuit board 40 respectively, the second connecting point 294 of the column 222 aligns with the touching point 322. The pressing body 10 is attached to the resilient member 20, and the base rim 12 of the pressing body 10 resists the cover board 22 of the resilient member 20. The housing 50 defines an aperture 52, through which the protrusion 14 protrudes to outside, to facilitate pressing by a user of the protrusion 14 of the pressing body 10.
Referring to FIGS. 4 and 5, in use, the pressing body 10 is pressed, enabling the connecting wall 24 to be compressed. When the column 222 contacts and resists against the touching point 322, the second connecting point 294 electrically contacts the touching point 322. In this case, the conducting films 29 create an electrically conductive contact between the first terminals 42 and the second terminals 44, and the electronic device generates a first signal activating a first function mode. When the pressing body 10 is pressed to move further downwardly, the column 222 urges the touching point 322 downwardly until the touching point 322 resists against the third terminal 46. At this stage, the first terminals 42, the second terminals 44 and the third terminal 46 are all conductive. The electronic device generates a second signal activating a second function mode. When releasing the pressing body 10, the connecting wall 24 of the resilient member 20 restores to the original position by the releasing of the compressed force of the connecting wall 24.
It should be understood that the pressing body 10 can be omitted, and a pole of the cover board 22 arranged extending out from the aperture 52 of the housing 50.
It is to be understood that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of structures and functions of various embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the present invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Patent Grant
8071897
